- From: Murray Maloney <murray@muzmo.com>
- Date: Mon, 24 Aug 1998 12:52:02 -0400
- To: xml-names-issues@w3.org
- Cc: w3c-xml-wg@w3.org
Folks, I have long had difficulty with the namespace specification. It has taken me a while to sort out, for myself, what the problem is. But I now think that I am able to state it clearly. First, my working assumption is that the specification *should* be trying to define what the *name* of any XML object is. That is, for any element type, attribute, notation, entity, or PI, what is its fully-qualified name? Although some have argued that notations, entities and processing instructions do not require namespace-qualification, I disagree strongly with that assertion. Michael Sperberg-McQueen has written at length about recombinant DTDs which could be used to validate documents that employ namespaces. I think that it is vitally important to be able to refer to notations, entities and PIs in a namespace-unambiguous way. Part of the namespace spec deals with XML's namespace partitions, but does not state clearly all of the *parts of a name*, nor how those parts can be combined to yield a fully-qualified name for any XML object. I submit the following for the consideration of the editors of the namespace spec: Name parts In XML, the fully-qualified name of any XML object is considered to be composed of multiple parts, including: namespace prefix part The prefix attached to the object instance's name. namespace URI part The URI associated with the prefix object type part Depending on the object type, one of element, attribute, entity, notation, pi local name part The object's name. scope part For attributes only, the scope part is namespace, or element. For all other XML object types, the scope part is namespace. The default is namespace. context part For element-scoped attributes, the context part is the name of the host element. This field may be empty for XML objects other than element-scoped attributes. Future revisions of XML, and future schema languages may define new scopes, which may extend the applicability of the context part. In fact, XML 1.0 does not explicitly consider namespace-scoped attributes (aka global attributes), but common convention has led to their inclusion in this proposal. I further propose that the fully-qualified name of any XML objects is composed of the namespace URI part, followed by the object type part, scope part, conext part, and local name part. Thus, the fully qualified name of <foo:bar xmlns:foo="http://www.muzmo.com/foo"> is: http://www.muzmo.com/foo?name="element:bar::" or: http://www.muzmo.com/foo?name="element:bar" and, the fully-qualified name for the *color* attribute: <foo:bar color="red" xmlns:foo="http://www.muzmo.com/foo"> is: http://www.muzmo.com/foo?name="attribute:color:element:bar" but, the fully-qualified name of the *foo:size* attribute: <shoe foo:size="8" xmlns:foo="http://www.muzmo.com/foo"> is: http://www.muzmo.com/foo?name="attribute:size:namespace:" or: http://www.muzmo.com/foo?name="attribute:size" and, the fully-qualified name of the *foo:size* attribute: <foo:shoe foo:size="8" xmlns:foo="http://www.muzmo.com/foo"> is: http://www.muzmo.com/foo?name="attribute:size:namespace:" or: http://www.muzmo.com/foo?name="attribute:size" The specific syntax is not critical to the proposal. However, it is essential that the name parts be identified and an agreed protocol be defined for naming the names of XML objects. For example, the order of the name part fields could re-arranged, and a character other than ":" might be used as a field separator. Placement of the scope and context parts at the end has the advantage of allowing for some minimization as illustrated above. Regards, Murray P.S. The preceding is a simplification of a comparable set of rules for namespaces in an upcoming XML Schema Language submission from Veo Systems Inc. Murray Maloney, Esq. Phone: (905) 509-9120 Muzmo Communication Inc. Fax: (905) 509-8637 671 Cowan Circle Email: murray@muzmo.com Pickering, Ontario Email: murray@veosys.com Canada, L1W 3K6 Email: murray@yuri.org
Received on Monday, 24 August 1998 12:52:16 UTC